This invention pertains to refrigeration systems, and more particularly to a coupling mechanism for removably coupling an expansion device to a liquid refrigerant line in a refrigeration system.
In any refrigeration system, the necessity arises for performing preventive or emergency maintenance in the field. For example, one component that may require maintenance in the field is the expansion device or devices that throttle liquid refrigerant flowing in one direction and allow liquid refrigerant to flow uninterrupted in the opposite direction. These expansion devices can become clogged with foreign matter, thus preventing proper and efficient operation of the heat pump.
In some refrigeration systems, the expansion device is secured in place by brazing the device in the liquid refrigerant line between the two heat exchangers. Thus, one of the problems in performing maintenance is that the brazed portion needs to be cut through, or the liquid refrigerant line on either side of the expansion device must be cut through in order to provide access to the interior of the expansion device. After maintenance has been performed as necessary, the field maintenance operator must then rebraze the expansion device into the liquid refrigerant line, or rebraze the two cut portions of the refrigerant line.
When performed in the field, the above requirements of cutting through the brazed connection or the refrigerant pipe and rebrazing as necessary are time consuming, and can be difficult to perform in the field.
Other expansion devices in refrigeration systems attempt to circumvent the above problems by trying to connect the expansion device to the liquid refrigerant line in a removable manner. However, due to the metal-to-metal connection between the expansion device and the liquid refrigerant line, the potential for refrigerant leaks about the metal-to-metal connection are undesirably increased. The existence of any increased potential or possibility of refrigerant leak is unacceptable for obvious reasons.